


The Hardcore Otaku Third Born (Leviathan x F!Reader)

by Diavolosthots



Category: Shall We Date?: Obey Me!
Genre: Breeding, Double Dicks, Eggs, F/M, NSFW, Oviposition, heat - Freeform, somewhat dub-con
Language: English
Status: Completed
Published: 2021-03-18
Updated: 2021-03-18
Packaged: 2021-03-27 16:14:22
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 3,644
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/30125454
Author URL: https://archiveofourown.org/users/Diavolosthots/pseuds/Diavolosthots
Summary: I wrote this when I hit 3K on tumblr and basically it's levi in heat with very serpent like tendencies.
Relationships: Leviathan (Shall We Date?: Obey Me!) & Original Character(s), Leviathan (Shall We Date?: Obey Me!)/Original Female Character(s), Leviathan (Shall We Date?: Obey Me!)/Reader
Comments: 2
Kudos: 130





	1. Starting Off it went....

Another year, another heat spent alone. It was always like that for Levi, and after millennia spent alone, he has found a trick or another that kept him busy and satisfied for the entirety of his heat. He never liked taking strangers like his brothers; the fear of being rejected or being deemed weird for how he… mated, was just too strong. Even for demons, Leviathan was deemed as weird, as an outsider. He used to take partners, a long time ago, just for the process, but once the heat and the ecstasy of the cycle had worn off from both him and his partner, they would run away disgusted and confused, leaving him hurt and sulking. At some point, he couldn’t take it anymore and decided to just keep to himself. The first few hundred years or so were hard; he made Lucifer lock his door with a spell so he couldn’t escape because the primal need for a partner was way too strong, but it worked. When he found Ruri-chan, she became his ‘partner’ in a sense. He used the body pillow he owned of her, mixed with a fleshlight. It was weird to him at first, but it seemed to do the job. 

But of course nothing ever went the way he wanted it to go. You just had to come along and ruin it. You and your feminine scent. Your sweet nature. Your very… breedable body. A woman in her prime, ready to be taken by a suitable mate. He didn’t bother trying, really. You wouldn’t want him anyway, not when you find out that you’re breeding with a literal demon; a monster, a freak of nature. But it wasn’t up to him anymore. Not now. He told Lucifer to make sure the spell was on his door days before the heat even started, just in case you decided to show up and his body decided to jump into action before the actual cycle was supposed to happen; he couldn’t take that risk. Not with you. He cared about you too much. You, however, were worried about him. Of course, no one told you what was actually going on; demons don’t talk about their heats over sunday lunch. It’s private, personal… They just told you he was feeling unwell, that it was a disease humans don’t know but is deadly to them. Of course, even the threat of death wouldn’t keep you away. 

Big mistake. 

The minute you turned the door knob, he freaked out. Excitement ran through his body and all his nerve endings were on fire. He was in the middle of releasing himself, trying to find some kind of friction against that painful erection, and then you showed up. He smelled you. He always did. Why wasn’t the spell working?! He freaked out harder when the door tried to open, trying to run across the room and close it before your scent really drove him wild but by now you were already in the room, which had been darkened days ago. You shrieked when you saw him run toward you, half naked and in his demon form. You noticed he had his tail curl around his leg right now, like Satan so often does, but you didn’t know why. He did that because if he didn’t, his tail would’ve long wrapped around your leg and pushed you against the floor. “(Y/N)!” He was breathing heavily; his body was preparing for the process and it was amazing, to him, how even just the sight of you was enough to send him into such a state. 

“Levi! Are you okay?” No, no he wasn’t and he won’t be until you leave. “G-Get out…” He groaned, feeling his cocks twitch in his pants, which he quickly tried to cover. “Oh my! You don’t look good… come here. We’ll get you back to bed.” you reached your hand out, touching his naked shoulder, but the minute your hand made contact with his skin, something inside of him snapped. With clenched teeth, he growled at you, letting his tail unwrap and wrap back around your leg, pulling and tripping you until you were on the ground. You landed with a thud, groaning as the floor hit your back. His hands clenched and unclenched into fists, his breathing picking up when he sees you beneath him. “(Y/N)..” his forked tongue hissed your name, and he quickly covered his mouth, embarrassed by what he was doing, but his tail didn’t give him the satisfaction of apologizing, no. Instead, it had wrapped around your upper thigh, caressing over the pants you were wearing. 

His hand came out to push the door back shut before he jumped on top of you, careful not to actually crush you. His tongue, once again, came out to lick over your cheek and you shuddered beneath him “L-Levi…!” He whined in response, licking his own lips, “I told you to leave…” He dipped his head down, inhaling deeply by your neck; you just smelled so good and he was soooo…. Needy. His hand moved down to cup his bulge, rubbing over his cocks through the fabric while his tail flicked over your pants. You looked down, watching him rub himself and feeling that familiar wetness between your legs; he could smell that too. His lips crashed against yours hungrily, and you actually opened your mouth for him, feeling his forked tongue while he undid your pants and tore them off. “L-Levi!” you shivered when the cold air of his room hit your skin and he groaned out, pushing his hips back against his hand which was still rubbing him. He was getting impatient and the tail that was curled around your leg undid itself to lash out behind him. He wanted you; he needed you. 

Harshly, he spread your legs, tearing your panties off to feel between your folds; the slickness on his fingers made him sigh with content and had a warm spreading through his body; you were ready. Your body wanted his. It turned him on even more and his tail slithered back up to your entrance, testing it by pushing the tip in. You gasped in surprise, trying to close your legs at the foreign intrusion, but he didn’t let you. “Stay still. I’m going to… I need to…” he growled before he could even finish that sentence, flipping you over and pulling your ass back up toward him, that way you didn’t see his double, serpent like dicks when he pulled his boxers down, and it was easier to push his eggs inside of you. He groaned when he pushed his tail further in, feeling you clench around him. It was slick, sliding in easily, and you noticed too how swiftly it entered, barely filling you but still giving you the sensation of penetration. “W-what.. Levi it’s so...deep…” You whined out, trying to push yourself on all fours, but his hand on your back pushed you back down. 

“Stay still. It’s easier to.. Fill you this way…” He groaned at the sight of his tail inside you, feeling the eggs try to push out of his tail. He groaned, pleasure seething through him as he grabbed one of his cocks and began to stroke it while his tail thrusted in and out of you. He made sure to push up against your cervix, moaning loudly when the eggs came out one by one and his tail pushed them straight into your womb.They were just eggs right now; still unfertilized. But that’s what the next part of his heat was for. You gasped in shock, bringing one of your hands to your stomach as you felt yourself be filled. Your body… it was just accepting it, taking it hungrily and the way his tail thrusted, pumping as it laid the eggs inside of you, had you moaning in bliss and close to an orgasm. “L-levi…” you couldn’t really say anything, but Levi knew. He sped up his own movements to chase his release, growling as his hips bucked, but not yet. He pulled his tail back, watching some of the liquid that protected the eggs inside his tail drip out of you. 

He needed you now; he couldn't wait anymore. “W-what are those….” You rubbed over your lower abdomen, feeling them inside you, but you didn’t have much time to think. Levi spread your folds with his thumbs before pushing his top cock in, groaning in bliss at the feeling of your wetness. You felt his other cock rub over your clit and onto your lower abdomen with each thrust he delivered and a quick look down confirmed it. “T-two…?!” His nails dug into your hips, slammed them back against his as he thrusted, clouded by primal instincts and lust. He needed to cum; needed to fill you if he wanted to mate with you, and god he did. Your scent, your pheromones drove him wild and he growled again when he slammed into you, his cocks twitching as he thrusted fast. 

You moved against him on the floor, crying out with each passing thrust and the feeling of his other cock rubbing over your clit. He brought you over the edge without warning, your walls pulsating around his cock while you rode it out. “Fuck….” He cursed under his breath, pulling your hips back against his before releasing inside you, deep. He made sure to hit right against your cervix, shooting his seed right into your womb and onto his eggs with a heavy breath. He was still rock hard, twitching and whining softly when his other cock released too, this time on the floor. He hated it; hated how it went to waste, and his eyes turned dark when he flipped you again.

You groaned when you landed on your back, feeling him pull back a little, just enough so he could guide his other dick toward your entrance too, “w-wait levi..!” You didn’t know if you could take it, but excitement rushed through you and when his other tip pushed in too, filling you up as well, all you could really do was cry out and arch your back. He moaned loudly when he bottomed out, taking your legs and pushing them on either side of your head so he could reach deeper, “mine…” he growled. His possessiveness was turning you on and you couldn’t help the clench that followed. 

He thrusted again, the sound of your wet cunt and his thrusts mixed in the room with your moans. His tail slithered back up to wrap around your waist, his hand making quick work on your top and bra. His tongue came back out at the sight of your breasts and he dipped his head down to let it swirl over them while his tail rubbed over your stomach with each thrust. You felt so full, feeling the eggs inside you and now his tail over them, as if it was encouraging you to take it. You whined in response, feeling him speed up again. You didn’t know if it was you or him but you felt so wet, allowing both of his dicks to enter with such ease and take you apart from the inside. 

His thrusts were bold, heavy, and quick. He pinned your hands down, squeezing tightly as he pounded you from above with clenched teeth, making sure he bottomed out with each thrust as he looked down at you with wondrous eyes. “Mine…” he repeated, snapping his hips forward. You cried out again, the pleasure too much as you shut your eyes tightly, feeling another orgasm approach. Your breasts were bouncing on your chest and he was quick to catch them with his hands, groping roughly as he brought you over the edge one more time. You arched your back into his hands, letting your own fly up and dig into his shoulders with a cry of his name. “L-leviathan!!” 

An inhuman growl escaped him as he felt your nails in his skin, and he slammed into you hard, releasing without warning. His thumbs were brushing over your nipples as he watched you, his cocks twitching inside you as he ensured you took all of his potent seed. “Going to… fertilize my eggs.. Your eggs.. Need you to be bred…” he hissed out, and you watched his tongue wiggle with each word as slow thrusts guided him through his orgasms. You could feel his hot seed spill inside you, your cervix clenching and sucking it all up. “B-breed…” it was more of a statement, although you meant for it to a question. 

You didn’t get much of a break, he already picked his thrusting back up, “again…” You groaned in response, feeling the eggs move inside you as he thrusted. The tail was still rubbing over your stomach, encouraging you to keep going as he filled you, over and over again, for days to come. 


	2. and it ended with ....

**Summary for the Chapter:**

> his season is over and levi fears he has fucked up

His heat, his breeding season, it seemed to last longer with you than it did before. He was fully prepared to breed you, to fill you with everything he had, while marking you as his. Your scent mixed with his own not long after he began and it drove him even wilder. The good thing about when he is like that is that he truly can’t stop, no matter how embarrassed he would usually be, and his instincts are taking over his usual self-conscious behavior, turning him into more of a freak than himself. Of course, this was spurted by his already existing feelings for you. If he hadn’t already found you attractive before, and hadn’t viewed you as a potential mate way before his season pushed in, he wouldn’t have lasted this long, but because his body, his heart, was aching for you every day before this, his season lasted way longer to ensure a thorough mating process. 

After he got you used to his second cock, he never pulled it out, either. You didn’t want him too. Even as exhaustion took a toll on your body, his hips only ever stopping enough to either give you water so you won’t die, or to push more of his eggs inside of you through his tail, you still loved the way his double dicks pushed into you, stretching you, filling you. “S-So much….” you didn’t even know where it came from, the energy you mean. He was rough with you, taking you in all the positions that he deemed as the perfect breeding position, and he came so much, so, so much… You didn’t know how he could produce that much without rest and by the time that he was finally done, after literal days, and you barely clung to life, it was only thanks to his tail that you didn’t fully leak out. He used it to plug you up, pushing the tip of it right into your cervix so none of his seed, none of his eggs, would slip out. You never really noticed. 

However, now that his season was over, he was freaking out. Exhaustion ended up rushing through him too and he never even made it off the floor with you, instead just grabbing a bunch of pillows to form a sort of nest around you and him, and then wrapped his tail tightly around you to keep you protected. It’s safe to say you and him slept for at least a day and he never changed position but when he finally did wake up again, he came face to face with you and he didn’t know how to handle that. You were right there, in his arms, his tail wrapped tightly around you. His eyes were wide and his face was flushed a deeper red than Diavolo’s hair, “oh no….. No, no, no, no!” He quickly undid himself from you, scrambling to get up and that’s when he realized he was still naked and so were you and he actually let out a squeal. The minute he pulled his tail out and away from you, he also noticed his cum seeping out and his eyes immediately landed on your stomach where his eggs were still lying. Markings and scratched were all over your body too and if it weren’t for the pure shock and feeling of having fucked up, he might’ve actually found this attractive as fuck, which, he quickly covered his cocks to keep it from being weird and changed back into his normal form. 

His squeal actually woke you up, though, but you have been trying to be quiet because you were still tired, “Levi…” Oh no! You noticed him! He isn’t going to survive this one chief, might as well die now. “I-I’m so sorry (Y/N)! I don’t know what got into me! Oh my father!!” He’s looking at you in shock and he’s trying to think of any believable excuse that he could come up with but all you’re doing is rolling onto your back and then… you’re rubbing over your stomach? He shrieks, “What are you doing?!” which makes you groan and cover your ears instead, “stop being so loud levi…” He’s starting to hyperventilate and he swears his heart is about to beat out of his chest and then you even go back to rubbing your stomach like no, no, no, no! “We need to get them out of you!!” He’s dropping to his knees so fast but right as he does, your eyes snap open and you clutch your stomach protectively, glaring at him. 

“Touch these eggs and I’ll fight you.” He pauses in cold blood, his eyes wide and his hands mere inches from your belly. “Are you crazy? If you keep them in there, they’ll… they’ll… they’re not even real kids! They like… tiny… serpent things…” he cringes at his own words, shame immediately rushing through him. They’re his kids, yes, but he still is ashamed of them because they’re not like him. Not now at least. Under just the right circumstances, maybe. Maybe they would turn into demons or a human or a hybrid of some sort but right now he needs to get them out of you, “(Y/N), listen to me… I-I know I … you… y-you probably hate me… b-but… we need to get them out! You need to….” A part of him hates that; a part of him feels very protective of them and he can’t bear to see his eggs go to waste, especially when you look so gorgeous, practically glowing, with them inside you.

“Hate you? I don’t hate you….” You smiled up at him, groaning as you tried to push yourself up and holding your stomach again when you felt the eggs move, “I don’t hate you… In a way, I’m kind of glad this happened… doesn’t this mean you like me too?” too?! You like him?! He’s back to blushing furiously and looking at you with wide eyes as shame and embarrassment continue to course through his veins, “l-l-l-like you too??? TOO?!” You laughed, nodding happily before looking at your arms and legs, feeling up your neck as well, “and you marked me… doesn’t that mean I’m yours now?” He’s blinking at you in shock and disbelief, “m-m-mine…??” He can’t get a sentence out, he really can’t. You nodded, taking one of his hands slowly, “yeah…. You claimed me as yours so thus I’m yours.” How can you say that so easily? You smiled sheepishly at him, taking his other hand too, “I was just waiting for you to make a move…. Maybe not this aggressively but I didn’t mind it… it… felt good. Really good… it still feels good…” You look down at your stomach and then use one hand to push the eggs around, laughing softly because it kind of tickles, “I want to be yours.”

If you weren’t holding his hand right now he might have passed out, and if you continue to rub over your stomach right now while he knows his eggs are inside, he might not be able to hide his boner much longer. “M-m-m-mine… you.. You… r-really?! You don’t think I’m weird?!” Now you actually laughed because hell no; that was probably the hottest sex you have ever had. “Levi you have two dicks and a tail and I can say that that was, 100% without a doubt, the best sex I ever had.” you weren’t lying and he knew that and maybe that freaked him out even more. “You want to be mine? You’re mine?! Mine!” He’s going through so many emotions right now and the only thing he knows how to do is grab your face and kiss you deeply, which you could only barely return, nodding against his lips, “yours…” 

He pulled back, his face still flushed and he’s looking anywhere but you right now, but he’s overwhelmed with joy, “mine…” he’s just letting it sink in, honestly. You didn’t reject him after he used your body as an incubator for his eggs, and you definitely didn’t reject his seed, like, he knows that much, and you even said that was the best sex you ever had! Problem is… that side of him doesn’t appear a lot, “I… uhm… we…. I can’t be a dad…. Yet…” He’s embarrassed to say that but he really, really wants those eggs out of you. “Please… they really won’t be babies… they’ll be like… serpents… snake things….” Making a real baby is much easier…. Well maybe not because it would have horns like him and he doubts you’d survive that pregnancy but he also doesn’t want to share you right away, anyway, so let’s hold off, okay? 

You pout softly, rubbing over your belly again before looking up at him, “can you fill me back up after?” Error. Levi has stopped functioning. 


End file.
